I upgraded to a new square taper crankset on a single-speed drivetrain and now the gap between my crank and the bottom bracket is bigger. That's because the cranks taper shape is different from the one I had before and I haven't changed the bottom bracket. This (along with a different shape of the crank) made the Q-factor bigger. I wanted to reduce it, so I ordered a new bottom bracket with a shorter spindle. I checked the measurement already and it's going to be all good with chainstay clearance. The question is:
How close can a square taper crank be to the bottom bracket? How small can the gap in the picture be?